There is an on-going need for genetic regulatory elements that direct, control or otherwise regulate expression of a transcribable nucleic acid (e.g., a transgene), for instance for use in a genetically engineered organism such as a plant. Genetic regulatory elements typically include 5′ untranslated sequences such as transcription initiation regions that contain transcription factors and RNA polymerase binding site(s), enhancer/silencer elements, a TATA box and a CAAT box together with 3′ polyadenylation sequences, transcription stop signals, translation start and stop signals, splice donor/acceptor sequences and the like.
For the purposes of genetic engineering, genetic regulatory elements are typically included in an expression vector or other engineered construct, to regulate expression of a transgene operably linked to the regulatory elements. Well known examples of promoters used in this fashion are CaMV35S promoter (Nagy et al. In: Biotechnology in plant science: relevance to agriculture in the eighties. Eds. Zaitlin et al. Academic Press, Orlando, 1985), maize ubiquitin promoter (Ubi; Christensen & Quail, Transgenic Research 5:213, 1996) and the Emu promoter (Last et al., Theor. Appl. Genet. 81581, 1991), though many others will be known to those of ordinary skill. Likewise, enhancers have been isolated from various sources for use in genetic engineering; these include the cauliflower mosaic virus (35S CaMV) enhancer, a figwort mosaic virus (FMV) enhancer, a peanut chlorotic streak caulimovirus (PClSV) enhancer, or mirabilis mosaic virus (MMV) enhancer.
There is an on-going need to identify genetic regulatory elements, such as enhancer domains, that can be harnessed to control expression of sequences operably linked thereto, for instance in heterologous nucleic acid molecules such as vectors and other engineered constructs.